/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * $Header:$
 */
package org.pentaho.di.trans.steps.webservices.wsdl;

import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

import java.util.ArrayList;
import java.util.List;

/**
 * Some DOM utility methods.
 */
public final class DomUtils {

    /**
     * <p>Returns the first child element with the given name. Returns
     * <code>null</code> if not found.</p>
     *
     * @param parent    parent element
     * @param localName name of the child element
     * @return child element, null if not found.
     */
    protected static Element getChildElementByName(Element parent, String localName) {
        NodeList children = parent.getChildNodes();

        for (int i = 0; i < children.getLength(); i++) {
            Node node = children.item(i);
            if (node.getNodeType() == Node.ELEMENT_NODE) {
                Element element = (Element) node;
                if (element.getLocalName().equals(localName)) {
                    return element;
                }
            }
        }
        return null;
    }

    /**
     * <p>Returns a list of child elements with the given
     * name. Returns an empty list if there are no such child
     * elements.</p>
     *
     * @param parent    parent element
     * @param localName Local name of the child element
     * @return child elements
     */
    protected static List<Element> getChildElementsByName(Element parent, String localName) {
        List<Element> elements = new ArrayList<Element>();

        NodeList children = parent.getChildNodes();

        for (int i = 0; i < children.getLength(); i++) {
            Node node = children.item(i);
            if (node.getNodeType() == Node.ELEMENT_NODE) {
                Element element = (Element) node;
                if (element.getLocalName().equals(localName)) {
                    elements.add(element);
                }
            }
        }
        return elements;
    }
}
